The present invention relates to an improvement in an automobile front pillar with shock absorbing capability.
An example of conventional automobile front pillars is illustrated in enlarged cross-section in FIG. 8 hereof. In the figure, reference characters Fr and Rr respectively represent front and rear directions of the automobile.
Front pillar 100 is composed of an inner frame 110 and an outer frame 120 joined with the inner frame 110 to provide a tubular configuration.
Inner frame 110 is formed of a sheet metal folded to provide a dish-shaped cross section and has a concave bottom portion 111. At opposite ends, the bottom portion 111 has joining portions 112, 113 in the form of flanges for joining with the outer frame 120.
Outer frame 120 is formed from a sheet metal folded to provide a generally U-shaped cross section and has a front portion 121 forming a convex part of the U shape. At opposite open ends, the outer frame 120 has joining portions 122, 123 in the form of flanges for joining with the companion joining portions 112, 113 of the inner frame 110.
Front pillar 100 has a tubular cross section provided by joining the joining portion 112 of the inner frame 110 with the joining portion 122 of the outer frame 120 and the joining portion 113 of the inner frame 110 with the joining portion 123 of the outer frame 120. The front pillar 100 forms part of the skeleton of an automobile side body.
Door weather strip 132 is provided on a door sash 131, carrying a door glass sheet 130, for achieving seal between the door sash 131 and the front pillar 100. A molding 133 is attached to the outer frame 120 of the front pillar 100. A separate sealing weather strip 135 and sealant 136 are disposed between the outer frame 120 and a windshield 134. An obstacle 140 is shown forwardly of the front pillar 100 by a two-dot-and-dash line.
Front pillar 100 has high rigidity because it forms part of the automobile side body as mentioned above. Due to the high rigidity of the front pillar 100, the obstacle 140 is imparted with a large shock or impact upon collision against the front portion 121 of the outer frame 120. Thus, where priority should be given to the protection of the obstacle 140, it becomes necessary to decrease the rigidity of the front pillar 100. However, decreasing the rigidity of the front pillar 100 results in an automobile body with decreased rigidity, which may therefore be easily deformed upon turnover of the body. Consequently, there has been a demand for an automobile front pillar which retains its initially required rigidity but can sufficiently buffer a collision shock to the obstacle.
An example automobile front pillar in which arrangements are made for damping a collision shock to an obstacle is disclosed in Japanese Patent Laid-Open Publication No. HEI9-39833 entitled xe2x80x9cAUTOMOBILE FRONT PILLARxe2x80x9d. The disclosed automobile front pillar includes a shock damping panel provided at a front part of an outer frame forming part of a pillar body.
However, the front pillar is obtained by the mere addition of the shock damping panel to a conventional front pillar. Consequently, when the obstacle collides against the pillar body through the shock damping panel, shock energy arising from the collision is damped by only the deformed shock damping panel. There is no means left for absorbing shock energy arising after the collision reaches the pillar body. Hence, sufficient damping of the shock to the obstacle cannot be achieved in the disclosed front pillar structure. To sum up, the pillar body of the disclosed front pillar structure has rigidity as inherently required therein but no arrangements are provided in the pillar body for damping the collision shock, arising after collision of the obstacle against the pillar body, to the obstacle.
It is therefore an object of the present invention to provide an automobile front pillar which has rigidity as inherently required therein and can sufficiently damp a shock, arising from the collision of an obstacle with the front pillar, from the obstacle.
According to the present invention, there is provided an automobile front pillar which includes, at a portion thereof positioned closely to a passenger compartment of an automobile, a weak portion for initiating the buckling of the front pillar upon application of a shock to that part of the front pillar positioned remotely from the compartment. In this arrangement, when an obstacle collides with the front pillar portion positioned remotely from the compartment, the weak portion collapses by the resulting collision shock to cause the front pillar to buckle. The collision shock is partly absorbed by the buckling front pillar. As a result, the shock applied to the obstacle is significantly damped. The weak portion is desirably covered by a cover so that it may not be exposed to view from the passenger compartment.
Preferably, the front pillar portion positioned remotely from the passenger compartment includes at its front part a flat portion having a protecting member with shock absorbing capability. The protecting member absorbs an initial part of the collision shock before the front pillar buckling begins, thereby effectively damping the shock applied to the obstacle. In addition, a shock damping member forte absorbing part of the shock may be provided within the front pillar so as to minimize the shock to the obstacle.
In a desired form, the front pillar comprises an inner frame positioned closely to the passenger compartment and an outer frame joined with the inner frame and having a portion positioned remotely from the passenger compartment. The weak portion may be provided in the inner frame. Alternatively, the weak portion may be provided in that part of the outer frame positioned closely to the passenger compartment.
It is preferred that the inner frame includes a reinforcing member attached thereto so that the front pillar can maintain its inherent rigidity. In a preferred form, the reinforcing member comprises a reinforcing pipe and a reinforcing plate attached to the inner frame.